4. Physiologic activity formed
when there is normal
occlusion in a cyclic
movement
a complex function that
uses not only the muscles,
teeth, periodontal supportive
structures but also the lips
cheeks tongue palate and
salivary glands
it consists of a number of
chewing strokes
Mastication
5. Mastication
Purposes:
1. Physiologic transformation of food
2. Enhances growth and development of the dento-
alveolar structures through stimulation
3. Stimulates salivary flow (which in turn maintain
oral hygiene)
4. Vitalization of food increase appetite
5. Protection of food from undesirable food
components
6. Helps further develop or allow jaw bone to grow
6. It is the rhythmic and well-controlled separation
and closure of the maxillary and mandibular teeth
Each stroke has a tear-shaped movement pattern.
Divided into:
**Opening
Crushing Phase
**Closing
Grinding Phase
7. Mandible drops
down from the
Intercuspal
position (ICP)
to a point
where the
incisal edges of
the teeth are
about 16 to 18
mm apart.
It then moves laterally 5-
6 mm from the midline.
OPENING PHASE
8. The buccal cusps of the Md teeth are almost
directly under the buccal cusps of the Mx teeth
on the side the mandible was shifted.
Mandible is
guided by the occlusal
surfaces back to the
intercuspal position
which causes the cuspal
inclines of the teeth to
pass across each other,
permitting shearing and
grinding .
CLOSING PHASE
9. When food is initially introduced into the mouth,
amount of lateral movement is greater and
becomes lesser as food is broken down.
The harder the food, the more
lateral the closure strokes
become and the more chewing
strokes needed
Chewing Stroke
FRONTAL VIEW
10. 1. GLIDING – occurs as the cuspal inclines pass by
each other during the opening and grinding
phases of mastication
2. SINGLE – occurs in the maximum intercuspation
194 ms – average length of time for tooth contact
while during mastication
11. Maximum biting force varies from individual to
individual.
MALE
118 to142 lb (53.6 to 64.4 kg)
FEMALE
79 to 99 lb (35.8 to 44.9 kg)
12. Maximum amount of force applied to molar is
usually several times that can be applied to an
incisor.
Central Incisor
29 to 51 lb
(13.2 to 23.1 kg)
1st molar
91 to 198 lb
(41.3 to 89.8 kg)
13. With age up to adolescence
With practice and exercise
Persons with marked
divergence of the maxilla
and mandible
14. LIPS guide, control intake and seal
food.
TONGUE plays a major role in taste
and maneuvering the food inside the
oral cavity. It also helps in dividing
soft foods and in sweeping the food
debris after eating.
CHEEKS (buccinator muscles)
repositions the food on the buccal
sides.
15.
16. aka “Deglutition”; an innate function
the series of coordinated muscle contraction
that moves a bolus of food from the oral cavity
through the esophagus to the stomach.
The decision to swallow depends on several
factors:
•Degree of fineness of the food
•Intensity of the taste extracted
•Degree of lubrication of the bolus
17. 1. INFANTILE / VISCERAL
SWALLOW
Characterisitics:
1. Lips are sealed and appear stiff
2. Tongue is abnormally large and is caught between
maxillary and mandibular gumpads
3. There is no harmonious relationship between the maxilla
and the mandible
4. Absence of normal seal
5. There is no harmonious relationship between cranial and
facial structures
18. 2. SOMATIC SWALLOW
Characterisitics:
1. Presence of normal seal
2. Presence of normal occlusion
3. Tongue is inside oral cavity
4. There is normal antero-posterior relationship betweeen
maxilla and mandible
5. There is harmonious relationship between the cranial and
facial structure
19. OVERRETENTION OF INFANTILE SWALLOW
Causes:
1. Lack of tooth support due to poor tooth position
or arch relationship.
2. Discomfort during tooth contact due to caries or
tooth sensitivity
EFFECTS:
1. Labial displacement of the anterior teeth by
powerful tongue muscle (Anterior Open Bite)
21. Voluntary
Begins with selective parting
of the masticated food
Into mass or bolus by
tongue
Bolus placed on dorsum of
tongue and pressed on
the hard palate while the
tip of tongue rest on the
Incisors.
Lips are sealed, teeth brought
together.
Reflex wave of contraction in
the tongue caused by
food on palatal mucosa
presses bolus backward.
22. Once the bolus reaches the pharynx, a
peristaltic wave caused by contraction of
the pharyngeal constrictor muscles carries
it down to esophagus.
The soft palate touches the posterior
pharyngeal wall sealing off the nasal
passages.
Phrayngeal orifices of the eustachian
tubes open
Oral and Pharyngeal phases of
swallow together last for 1s.
23. Consists of passing of the bolus
through the length of the esophagus
to the stomach by Peristaltic waves
(6-7s)
The Cardiac sphincter relaxes as
the bolus approaches and let it enters
the stomach.
Upper section of esophagus is
composed of voluntary muscles while
lower portion is entirely with
involuntary muscles.
24. According to Studies:
590 cycles --- 24-hr period
146 cycles --- eating
394 cycles --- between meals while awake
50 cycles --- sleep
**Lower levels of salivary flow during
sleep result in less need to swallow
25. DYSPHAGIA – difficulty in swallowing
ODYNOPHAGIA – painful swallowing
APHAGIA – absence of swallowing due to paralysis of muscles
of deglutition or mastication
Abnormal growth of esophagus – cancer, tumor, outgrowth
or overgroath
26.
27. 3rd major function of the stomatognathic
system
It occurs when a volume of air is forced
from the lungs by the diaphragm through the
larynx and the oral cavity.
Controlled contraction and relaxation of the
larynx create a sound with desired PITCH.
It occurs during the expiration stage of
respiration
28. Afferent mechanism – those involved in hearing and
sight
Association areas – those involved in:
A. seat of learning and memory
B. seat of habits and condition habits
C. cerebral cortex and molar centers
Efferent mechanism – involves the nerves that
supplies the muscles involved in speech
29. RESPIRATION –
simultaneous
breathing to have stream
of air from lungs is
needed to produces
vibration PHONATION –
actual production
of speech sounds
RESONANCE –
process by which
sound is intensified or
amplified
30. ARTICULATION – breaking up of sound and
modification of sounds from lungs, this involves the
complex conditioning movements of:
a. Lips
b. Cheeks
c. Palate
d. Tongue
e. Posterior laryngeal wall
31. By varying the relationships of the lips and tongue
to the palate and teeth, a variety of sounds can be
produced.
M, B, P ---- formed by lips
S -------- by teeth( in close approximation)
D -------- tongue and palate
TH -------- tongue to maxillary incisors
F, V ------- lip to incisal edges of maxillary teeth
K, G ------- posterior portion of thee tongue to
soft palate
34. It is a continuous process closely associated
with deglutition.
This is also referred to as ventilation where in
there is an entrance of oxygen and release of
carbon dioxide
37. 1. Presence of normal seal
2. Normal atmospheric pressure
3. Normal TMJ
4. Normal occlusion
5. Normal antero-posterior relationship of maxilla
and mandible
6. Tongue is kept within the oral cavity
7. Establishment of physiologic rest position
38. CAUSES:
• chronic allergies
• tonsil hypertrophy
• nasal polyps
• deviated nasal septum
• constricted upper airways
• a backward positioned lower jaw caused by
thumb sucking
• excessive pacifier use or insufficient suckling
as an infant
Notas do Editor
SECONDARY FXNS: Respiration and Expression of Emotions
In some subjests, the number of chewing strokes does not change with the varying consistency of food.
Tooth contacts occur during late stages of mastication.
Increased biting force in eskimo populationRather than those with parallel maxilla and mandible
However, Presence of tongue thrusting codition does not necessarily lead to altered teeth position